p. 419: Change the description of the // abbreviated step to the following:
All descendants of the context node and the context node itself unless // occurs at the beginning of the expression, in which case this refers to all descendants of the root node and the root node itself. Never used in isolation. Must be followed by a location step.
P. 424: In the heading for the floor function, change "floor(3e)" to "floor()". I have no idea where that 3e came from.